Stereo-cinematograph.



E. CERVENKA.

STEREO CINEMATOGRAPH.

APPLICAHON man can 19. 2911.

Patented Dec. 14,1915, fi 4:. $7 5 w H 6 a f 0 6 w 0 w. WW aw Ma EMANUEL CEBVENKA, OF PARIS, FRANCE.

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Specification of Letters Patent. Patented Dec. 14, 1915;

Application filed October 19 1911. Serial No. 655,531.

To all whom it may concern:

Be it .known that I, EMANUEL CERVENKA, a subject of the Emperor of Austria-Hungary, residing at Par1s,2 Impasse Mazagran,

in the Republic of France, engineer, have invented certain newand useful Improvements in Stereo-Cinematographs, of which the following is a specification.

This invention relates to a stereo-cinematograph, that is to an apparatus for taking and projecting cinematograph films giving directly the illusion of relief, without the aid' of any member interposed between the stereographic picture and the eye of the spectator. Such apparatus is essentiallly distinguished from any usual cinematograph by the presence of a. device which produces the deflection in opposite directions alternatively of the luminous rays which go from the object cinematographed to the film when the views are being taken, or from the film to the picture when the relief is being made,

so that the successive views seem to be taken from different points. The effect thus produced on the eyes of the Spectators may be compared to that which would be observed in looking at a fixed object alternatively with both eyes in quick succession.

The device serving to deflect the luminous rays alternatively to the right and to the left may be constructed in various ways in that drawings show diagrammatically severalv embodiments of this invention.

Figure 1 is a diagrammatic plan view of the cinematograph provided with a series or set of mirrors giving the stereoscopic effect. Fig. 2 is a front elevation of a cinematograph provided with such a set of mirrors, with a part broken away. Fig. 3 is a vertical section of such apparatus. Fig. 4.- shows on a larger scale a cam serving to move one of the mirrors. Fig. 5 shows a portion of the film and the position of a. series of successive pictures on such film. Fig. 6 is a plan view of a series or set of prisms which may replace such series or sets of'mirrors. Figs. 7 and 8 represent a vertical section and a plan view of an apparatus, the object-glass of which is movable. Fig.1) is a diagrammatic plan view of an apparatus, of which.

the chamber, the obturator and the film move horizontally.

lVith reference to Figs. 1 to 8, a designates a usual cinematograph apparatus the objectglass 1) of which is fixed and in which the i film 0 moves step bystep and vertically behind the object-glass in the well known man ner. In front of the object-glass is located a fixed mirror 12 sloping laterally; in parallellism with the latter is located a movable mirror 6 which is successively brought toward and then away from the mirror d,- such mirror e occupies successively for instance the positions e, 6 e 6 e, etc., while the film is moved forward step by step. f designating any object, it will be seen that when the mirror e is in the position shown in full lines, the luminous ray going from the point f of such object to the center of the object-glass follows the path 7 g h b; the object f is seen from the object-glass in the mirrors as if the object-glass were located at and the mirrors were withdrawn, the point b being symmetric with regard to e of the point I)", which is itself symmetric with regard to d of the center of the objectglass b. On the mirror e being moved to 6 the luminous ray follows the path f g' 72. b and the object is seen as if the object-glass were at 6 the mirrors being withdrawn. Likewise, on the mirror being brought to 0 the object 7 is seen as if the object-glass were at b So the successive pictures on the film 0 can be seen from diiferent points. What is meant here by point of view is that which is understood by the eye in perspective, and that which corresponds to the center of the object-glass in ordinary photography. It is to be noted that such pictures are slightly displaced transversely with regard to one another (see Fig. 5) but as the device operates in the same manner in taking views as for producing relief, it will be understood that the projections of the pictures will naturally assume one and the same position; the only resulting abnormal effect will be the alternative displacement of the point of view from right to left, which Will give the required efi'ect, although the spectators see that with such device the virtual point of view (91 b b is displaced obliquely with regard to the object-glass, but without producan axle j such lever being controlled by a cam groove k which turns in accordance with the wheel having a Maltese cross Z0 of the usual mechanism which servesto advance the film. To each advance made by the film there corresponds on the cam a part of the right hand groove, so that the mirror 6 and the film remain stationary at the same time as well as move at the same time. The stroke of the mirror 6 can be regulated by displacing the rocking axle j in the slideways, not shown in the drawings. In this embodiment of the invention, the mirror 6 is supposed to assume besides the extreme positions to the right and left, an intermediate position of rest, but it must be understood that the latter position may be dispensed with. Without changing in any. way the operation of the above described apparatus, for the mirrors d 6 may be substituted the total deflection prisms (.1 e (see Fig. 6), one of which is fixed and the other movable.

Figs. 7 and 8 show a modified form of the apparatus in which neither a mirror nor a prism is interposed between the object-glass and the animated object of the picture to be projected; in such modification, it is the object-glass?) which reciprocates laterally so that the perspective point of view passes alternatively from the position b to the position b and vice versa. For such purpose,

the object-glass may be mounted in horizontal slide-ways 2' and be movedby a rocking lever as the movable mirror was in the previous embodlment. With such a device, the

film may move only in the vertical direction,

so that the pictures thereon are successively measea displaced to the right and left; but the support of the film may also be displaced translaterally, a movable mirror directed parallelly to the said fixed mirror and means operatively connected to the means for advancing the film whereby the movable mirror is moved alternately away from and toward the said fixed mirror in .accordance or register with the advancing movements ofrthe film, substantially as described and for the purpose specific 2. In a cinematograph, the combination of means for advancing the film step by step, a fixed mirror located in front of the objectglass of the cinemato-graph and, inclined laterally, a movable mirror directed parallelly to the fixed mirror, and means operatively connected tothe means for advancing the film whereby the movable mirror is moved alternately away from and toward the fixed mirror in such a manner that in each of its forward and backward movements the said movable mirror is advanced step by step in accordance with the advancing movements of the film.

In testimony that l claim the foregoing as my invention, 1 have signed my name in presence of two subscribing witnesses.

EMANUEL GERVENKA.

Witnesses H. C. Coxn,

MAURICE Roux. 

